Static-influence electric machine.



No. 882,508. PATENTED MAR. .1 7, 1908.

H. WOMMELSDORF. I STATIC INFLUENCE ELECTRIC MACHINE.

APPLICATION FILED APR. 27, 1906.

I Jciarzzez THE uomzls PETERS co. wlsmmzrou, p. c.-

HEINRICH WOMMELSDORF, OF CHARLOTTENBURG, GERMANY.

STATIC-INFLUENCEEELECTRId MACHINE.

Specification of Letters Patent.

Patented March 17, 1908.

Application filedIAprilIZ'Y, 1906. Serial No. 314,011.

To all whom it may concern:

Be it known that I, HEINRICH WoM ELs- DORF, a subject of the King ofPrussia, German Emperor, and resident of 15 Fraunhoferstrasse,Charlottenburg, near Berlin, German Empire, engineer, have inventedcertain new and useful Improvements in Static-Influence ElectricMachines, of which the following is an exact specification.

My invention relates to improvements in static influence electricmachines (influence and multiple or condenser machines) and is intendedto provide a .machine by means of which the quantity of electricityproduced per revolution of the energizing plate is highly increased overthe arrangements which have become known hitherto.

As known in machines of theaforementioned type the metallic inductors orcarriers or sectors are secured either to an insulating disk or embeddedbetween two insulating plates lying closely upon each other. In theformer case the inductors are in contact in part with air or a gaseousfluid and in the latter case the inductors or carriers are inclosed bythe solid insulating material.

Experiments have shown that where the number of sectors in the disk hasbeen considerable and equal the following results have been obtained inthe following cases:

Firstly, when the sectors are in contact with the atmosphere, *6. e. inthe case where the sectors are pasted on to the disks, the greatestquantity of electricity is obtained when an accurately determined areaof sectors is employed and an accurately deter mined. interval occursbetween them. Secondly, in the case of the inducting sectors beinginclosed in the body of the insulating material experiment has shownthat the amount of electricity produced is increased if the surface ofthe conductors is increased and their distance apart diminished. Thesecomparisons are of course made on the assum' tion that the number ofinducting sectors emp oyed remains the same in both cases.

By increasing the surface adjacent conductors are brought very closetogether so that the tension on the dielectric becomes very severe. Tomake the dielectric capable of withstanding such high tensions it hasbeen found necessary to manufacture it by rolling, as casting the-dislgaround the secparts or pressed togetherlayers of the dielec- I Itric or disk. This result is obtained by interposing a non-conductor inthe direct path it. c. the geometrical straight-line between adjacentconductors in a circumferential direction and such interposition maybeeffected in various ways but I shall describe only one as an example. 1

Figure 1 is a fragmentary side view of an energizing plate according tomy invention. Fig. 2 is a fragmentary sectional cross view on line abofFig. 1. Fig. 3 showsafurther modification in a fragmentary crosssection. Fig. 4 is a fragmentary side-view of an energizing plateprovided with an external protective layer. Figs. 5 and 6 show thedisk-constru ctions according to Figs. 2 and 8 respectively inconnection with the aforementioned protective layer. i

In the figures c and f designate the plates or disks of insulatingmaterial, and s the metallic inductors or carriers or sectors, which areperfectly inclosed by the said disks 6 and f; t is the insulatingmaterial situated between the sectors 8, and being made so as toincrease the extension of the separating surfaces between two successivedisks 8 s.

Avery convenient constructional form in view to an easy, cheap and exactproduction, is illustrated in the Figs. 1 and 2. In this structure twosuccessive inductors of tin foil or thin metal sheet are arranged ondifferent sides of an insulating disk i, thus effecting that an electricdischarge from the one sector 8 must pass by a longer way to the thirdsector 8 In Fig. 3 a constructional form is shown, in which instead ofone insulating plate '5 several plates separating the inductors,carriers or sectors are situated one above the other thus causing thatthe first inductor s is followed taken along the separating face by thefourth sector 8 In order to impart to the plate, built up of a number ofparts, a greater mechanical rigidity, it is preferable to produce thedisks e and f and the intermediate layer of non;

vulcanized india-rubber, rolled in plate form, to provide them withinductors, to join and then to compress and vulcanize the parts. Thesaid parts can also be made of any other insulating material and can becombined strongly with each other by any suitable means. The electricityis taken off from the inductors, carriers or sectors preferably by meansof metallic studs k (as seen in Fig. 5) or as usual in condensermachines by metal bars projecting through the plates and touching theinductors. Practice with such plates of ebonite have shown that whilethe disks are prevented from becoming useless by interior discharge, thedisks nevertheless become useless for another reason. By reason of theelectrical discharge on the back on the disk, i. e. by the gasesproduced thereby, and consisting of ozone and oxids of nitrogen, agradual chemical decomposition of the face of the ebonite occurs,whereby the back sides are rendered current conducting, and theinduction machine is rendered useless. Also in using other insulatingmaterial; having excellent me chanical and electrical properties,similar defects occur.

In order to be enabled notwithstanding to use such materials for theproduction of plates, owing to the fact that experiments havedemonstrated that the decomposition of the plates practically takesplace only on the surface, the plates according to this invention areprovided with a layer (1 (to be seen in Figs. 4, 5 and 6), the surfaceof which keeps its insulating power continuously or for a longer timethan the surface of the plate itself.

Many attempts have shown that )referably such a layer is made of a thince luloid disk, fixed to the plate of ebonite by a suit able bindingmeans, or in any other way. In other cases it is sufficient to apply theinsulating material having the higher capacity of resistance in the formof a solution and then to dry it. For example the ebonite plate can becoated with Zapon or a solution of camphor or celluloid in acetone,amyl-acetate and the like, whereby a plate is produced having a greaterconstancy than the plates consisting only of ebonite.

This process differs essentially, with regard to the purpose intended,as well as to the means employed, from the known lacquering of the glassplates of the induction machines. These plates, as known, are coatedwith a shellac dissolution in order to prevent them from becomingcovered with moisture at their surfaces. In this case on the contrarythe glass is the body which is indecompos able or indestructible, andvthe shellac is the body which is rendered gradually useless andcurrent-comlucting by the electrical discharging, that is to say by thegases produced thereby. In no case a glass surface continuouslymaintaining its insulating power could be exceeded by a lacquer coatingin this view, whereas in the present invention the contrary takes place.

Having thus fully described the nature of my invention, what I desire tosecure by Letters Patent of the United States is 1. In an influencemachine, a disk consisting of two insulating side-plates, conductinginductors or sectors situated between the "side-plates, and of aninsulating plate carrying alternatively the inductors f lowing one tothe other in tangential direction, on different sides.

2. In an influence machine, a disk consisting of two insulatingside-plates, and provided on its outside with a layer, the face of whichlayer retains its insulating power under the influence of electricaldischarge or of the gases produced thereby, continuously or for a longertime than the surface of the disk, conducting inductors or sectorssituated between the side-plates and of an insulating plate carryingalternatively the inductors folowing one to the other in tangentialdirection, on different sides.

3. In an influence machine, a disk consisting of two side-plates ofebonite and provided on its outside with a layer of celluloid,conducting inductors or sectors situated between said sideplates and ofan insulating plate carrying alternatively the inductors following oneto the other in tangential direction, on different sides.

4. In an influence machine a disk consisting of a plurality ofinsulating plates arranged one above the other, and conductingconductors or carriers or sectors following one upon the other in acircle, two successive sectors being situated. between differentinsulating plates,

5. In an influence machine, a disk consisting of a layer on the outsideof the disk, the face of which layer retains its insulating power underthe influence of electrical discharge or of the gases produced therebycon tinuously or for a longer time than the surface of the disk, aplurality of insulating plates arranged one above the other andconducting sectors following one upon the other in a circle, twosuccessive sectors being situated between difl'erent insulating plates.

6. In an influence machine, a disk consisting of a plurality of eboniteplates, arranged one above the other, conducting sectors following oneupon the other in a circle, two successive sectors being situatedbetween different ebonite plates, and a layer on the outi In Witnesswhereof I have hereunto set iny side of the disk, the face of whichlayer rehand in the presence of two Witnesses. tains its insulatingpower under the influence 'HEINRICH VVOMMELSDORF of electrical dischargeor of the gases pro- 5 duced thereby continuously or for a'longerWitnesses:

time than the surface of the disk, and which HENRY HASPER,

layer consists of celluloid. W OLDEMAR HAUPT.

